U.S. patent application number 11/119926 was filed with the patent office on 2005-09-08 for ink jet recording material.
Invention is credited to Lingier, Stefaan, Loccufier, Johan.
Application Number | 20050196554 11/119926 |
Document ID | / |
Family ID | 31998505 |
Filed Date | 2005-09-08 |
United States Patent
Application |
20050196554 |
Kind Code |
A1 |
Loccufier, Johan ; et
al. |
September 8, 2005 |
Ink jet recording material
Abstract
An ink jet recording material is disclosed comprising a support
and at least one binder containing ink-receiving layer, further
containing a light-stabilizing compound according to following
general formula (I): A-L-R (I) wherein, A is represented by
following formula: 1 the symbols of which are defined in the claims
and description. The finished ink jet image shows an improved
light-fastness.
Inventors: |
Loccufier, Johan;
(Zwijnaarde, BE) ; Lingier, Stefaan; (Assenede,
BE) |
Correspondence
Address: |
NEXSEN PRUETT JACOBS & POLLARD
201 W MCBEE AVENUE
SUITE 400
GREENVILLE
SC
29601
US
|
Family ID: |
31998505 |
Appl. No.: |
11/119926 |
Filed: |
May 2, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11119926 |
May 2, 2005 |
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10657466 |
Sep 8, 2003 |
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60412837 |
Sep 23, 2002 |
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Current U.S.
Class: |
428/32.1 |
Current CPC
Class: |
C07D 211/72 20130101;
C07D 405/12 20130101; C07D 211/94 20130101; B41M 5/5254 20130101;
C07D 211/58 20130101; C07D 207/16 20130101; B41M 5/5218 20130101;
B41M 5/5227 20130101; C07D 207/46 20130101 |
Class at
Publication: |
428/032.1 |
International
Class: |
B41M 005/00 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 11, 2002 |
EP |
02102340.3 |
Claims
1-7. (canceled)
8. A compound represented by formula (II): 50wherein, R.sup.1 to
R.sup.4 independently represent a substituted or unsubstituted C1
to C6 aliphatic group; X is selected from the group consisting of a
hydrogen, a substituted or unsubstituted aliphatic group, an acyl
group, an oxy radical, a hydroxyl group, an alkoxy group an
--OSO.sub.2-alkyl group, and an acyloxy group; L is a divalent
linking group, linked to the six-membered ring with a single or a
double bond, wherein said divalent linking group comprises a
nitrogen-nitrogen or nitrogen-oxygen bond; and R represents a
non-aromatic moiety comprising at least two hydroxyl groups.
9. Compound according to claim 8 represented by following formula
(V): 51wherein, R.sup.1 to R.sup.4 independently represent a
substituted or unsubstituted C1 to C6 aliphatic group; X is
selected from the group consisting of a hydrogen, a substituted or
unsubstituted aliphatic group, an acyl group, an oxy radical, a
hydroxyl group, an alkoxy group an --OSO.sub.2-alkyl group, and an
acyloxy group; Y represents an oxygen or NR.sup.5; R.sup.5 is
selected from the group consisting of a hydrogen, a substituted or
unsubstituted, saturated or unsaturated aliphatic group, a
substituted or unsubstituted aromatic group, a substituted or
unsubstituted hetero-aromatic group, and an acyl group; and R
represents a non-aromatic moiety comprising at least two hydroxyl
groups.
10. A compound according to claim 8, wherein said compound (I) is
selected from the group consisting of 52
11. A compound according to claim 9, wherein said compound (II) is
selected from the group consisting of 53545556
Description
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS
[0001] This application is a divisional of U.S. patent application
Ser. No. 10/657,466 which claims the benefit of U.S. Provisional
Application No. 60/412,837 filed Sep. 23, 2002, which is
incorporated by reference. In addition, this application claims the
benefit of European Application No. 02102340.3 filed Sep. 11, 2002,
which is also incorporated by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to an ink jet recording
material having an improved stabilization of the finished image
against color fading due to light.
BACKGROUND OF THE INVENTION
[0003] In the majority of applications printing proceeds by
pressure contact of an ink-laden printing form with an
ink-receiving material which is usually plain paper. The most
frequently used impact printing technique is known as lithographic
printing based on the selective acceptance of oleophilic ink on a
suitable receptor.
[0004] In recent times however so-called non-impact printing
systems have replaced classical pressure-contact printing to some
extent for specific applications. A survey is given e.g. in the
book "Principles of Non Impact Printing" by Jerome L. Johnson
(1986), Palatino Press, Irvine, Calif. 92715, USA.
[0005] Among non-impact printing techniques ink jet printing has
become a popular technique because of its simplicity, convenience
and low cost. Especially in those instances where a limited edition
of the printed matter is needed ink jet printing has become a
technology of choice. A recent survey on progress and trends in ink
jet printing technology is given by Hue P. Le in Journal of Imaging
Science and Technology Vol. 42 (1), January/February 1998.
[0006] In ink jet printing tiny drops of ink fluid are projected
directly onto an ink receptor surface without physical contact
between the printing device and the receptor. The printing device
stores the printing data electronically and controls a mechanism
for ejecting the drops image-wise. Printing is accomplished by
moving the print head across the paper or vice versa. Early patents
on ink jet printers include U.S. Pat. No. 3,739,393, U.S. Pat. No.
3,805,273 and U.S. Pat. No. 3,891,121.
[0007] The jetting of the ink droplets can be performed in several
different ways. In a first type of process a continuous droplet
stream is created by applying a pressure wave pattern. This process
is known as continuous ink jet printing. In a first embodiment the
droplet stream is divided into droplets that are electrostatically
charged, deflected and recollected, and into droplets that remain
uncharged, continue their way undeflected, and form the image.
Alternatively, the charged deflected stream forms the image and the
uncharged undeflected jet is recollected. In this variant of
continuous ink jet printing several jets are deflected to a
different degree and thus record the image (multideflection
system).
[0008] According to a second process the ink droplets can be
created "on demand" ("DOD" or "drop on demand" method) whereby the
printing device ejects the droplets only when they are used in
imaging on a receiver thereby avoiding the complexity of drop
charging, deflection hardware, and ink recollection. In
drop-on-demand the ink droplet can be formed by means of a pressure
wave created by a mechanical motion of a piezoelectric transducer
(so-called "piezo method"), or by means of discrete thermal pushes
(so-called "bubble jet" method, or "thermal jet" method).
[0009] Ink compositions for ink jet typically include following
ingredients: dyes or pigments, water and/or organic solvents,
humectants such as glycols, detergents, thickeners, polymeric
binders, preservatives, etc. It will be readily understood that the
optimal composition of such an ink is dependent on the ink jetting
method used and on the nature of the substrate to be printed. The
ink compositions can be roughly divided in:
[0010] water based; the drying mechanism involves absorption,
penetration and evaporation;
[0011] oil based; the drying involves absorption and
penetration;
[0012] solvent based; the drying mechanism involves primarely
evaporation;
[0013] hot melt or phase change: the ink vehicle is liquid at the
ejection temperature but solid at room temperature; drying is
replaced by solidification;
[0014] UV-curable; drying is replaced by polymerization.
[0015] WO 01/020078 discloses a compound of any of formulas I to X,
or IA to XA 2345
[0016] or a product of one of the following reactions XI to XVI or
XIA to XVIA 678
[0017] U.S. Pat. No. 6,232,469 discloses
4-acylamino-2,2,6,6-tetramethylpi- peridine derivatives represented
by formula (A'): 9
[0018] wherein R.sub.1 represents a hydrogen atom, a hydroxyl
group, an oxyradical group, an aliphatic group, an acyl group, an
aliphatic oxy group or an acyloxy group; and R.sub.2' represents an
alkyl group or an alkenyl group having 3 to 7 carbon atoms and 2 to
6 hydroxyl groups, said alkyl or alkenyl group being unsubstituted
or substituted with an alkyl group. U.S. Pat. No. 6,232,469 further
discloses an antioxidant composition for color diffusion transfer
photographic materials or ink-jet dyes comprising the
4-acylamino-2,2,6,6-tetramethylpiperidine derivatives represented
by formula (A): 10
[0019] wherein R.sub.1 represents a hydrogen atom, a hydroxyl
group, an oxyradical group, an aliphatic group, an acyl group, an
aliphatic oxy group or an acyloxy group; and R.sub.2 represents an
alkyl group or an alkenyl group having 3 to 7 carbon atoms and 2 to
6 hydroxyl groups.
[0020] JP 61-146591 discloses an ink-jet recording medium that form
a recording image using aqueous ink that contains a water-soluble
dye, characterized in that the recording medium contains a hindered
amine type compound, in particular a molecule represented by
formula (I): 11
[0021] wherein R.sub.5 is a hydrogen atom or an alkyl group of
C.sub.1 to C.sub.8, a benzyl group, an allyl group or an acetyl
group and preferably a hydrogen atom or a methyl group; R.sub.1,
R.sub.2, R.sub.3 and R.sub.4 are lower alkyl groups, carbonyl
groups etc. and preferably methyl groups and/or ethyl groups. JP
61-146591 further discloses that if n=1, A is NH.sub.2, --OH,
.dbd.CH.sub.2, .dbd.O, --R, --OR, --OCO--R,
--NHCH.sub.2CH.sub.2CH.sub.2OCH.sub.3, --NHCSSH, phenyl,
--CH.dbd.CH.sub.2, (here R is an alkyl group), 12
[0022] It is known that the ink-receiving layers in ink-jet
recording elements must meet different stringent requirements:
[0023] the ink-receiving layer should have a high ink absorbing
capacity, so that the dots will not flow out and will not be
expanded more than is necessary to obtain a high optical
density;
[0024] the ink-receiving layer should have a high ink absorbing
speed (short ink drying time) so that the ink droplets will not
feather if smeared immediately after applying;
[0025] the ink dots that are applied to the ink-receiving layer
should be substantially round in shape and smooth at their
peripheries. The dot diameter must be constant and accurately
controlled;
[0026] the receiving layer must be readily wetted so that there is
no "puddling", i.e. coalescence of adjacent ink dots, and an
earlier absorbed ink drop should not show any "bleeding", i.e.
overlap with neighbouring or later placed dots;
[0027] transparent ink-jet recording elements must have a low
haze-value and be excellent in transmittance properties;
[0028] after being printed the image must have a good resistance
regarding water-fastness, light-fastness, and good endurance under
severe conditions of temperature and humidity;
[0029] the ink jet recording element may not show any curl or
sticky behaviour if stacked before or after being printed;
[0030] the ink jet recording element must be able to move smoothly
through different types of printers;
[0031] All these properties are often in a relation of trade-off.
It is difficult to satisfy them all at the same time.
[0032] A particular problem is the stability of the color densities
of the finished color ink jet image when exposed to light for a
longer period ("light-fastness"). As well-known by those skilled in
the art, the light fading of colorants is mainly due to an
oxidative decomposition of the colorant catalyzed by light, in
particular by the UV spectral part. Therefore, there is a permanent
need of more effective compounds, which stabilize the colorants of
the ink jet image against fading by light.
OBJECTS OF THE INVENTION
[0033] It is therefore an object of the present invention to
provide an ink jet recording material with an improvement in
light-fastness.
[0034] It is therefore a further object of the present invention to
provide a compound having light-stabilizing properties.
[0035] Further objects and advantages of the present invention will
become apparent from the description hereinafter.
SUMMARY OF THE INVENTION
[0036] It has been surprisingly found that when an ink jet
recording material contains a compound represented by formula (I):
A-L-R, wherein L is a divalent linking group, linked to the five-
or six-membered ring by one of the atoms of Z, optionally by a
double bond, characterized in that it comprises a nitrogen-nitrogen
or nitrogen-oxygen bond; R represents a non aromatic moiety
comprising at least two hydroxyl groups; and A is represented by
following formula: 13
[0037] where Z represents the necessary atoms to complete a five-
or six-membered ring, R.sup.1 to R.sup.4 independently represent a
substituted or unsubstituted C1 to C6 aliphatic group, X is
selected from the group consisting of a hydrogen, a substituted or
unsubstituted aliphatic group, an acyl group, an oxy radical, a
hydroxyl group, an alkoxy group, an --OSO.sub.2-alkyl group, and an
acyloxy group, exhibit a strong improvement in light-fastness.
[0038] Objects of the present invention are realized by providing
an ink jet recording material comprising a support and at least one
binder-containing ink-receiving layer, characterized in that said
at least one ink-receiving layer further contains a
light-stabilizing compound according to formula (I):
A-L-R (I)
[0039] wherein A is represented by following formula: 14
[0040] wherein Z represents the necessary atoms to complete a five-
or six-membered ring, R.sup.1 to R.sup.4 independently represent a
substituted or unsubstituted C1 to C6 aliphatic group, X is
selected from the group consisting of a hydrogen, a substituted or
unsubstituted aliphatic group, an acyl group, an oxy radical, a
hydroxyl group, an alkoxy group, an --OSO.sub.2-alkyl group, and an
acyloxy group; L is a divalent linking group, linked to the five-
or six-membered ring by one of the atoms of Z, optionally by a
double bond, wherein said divalent linking group comprises a
nitrogen-nitrogen or nitrogen-oxygen bond; and R represents a non
aromatic moiety comprising at least two hydroxyl groups.
[0041] Objects of the present invention are also realized by
providing a compound represented by following formula: 15
[0042] wherein R.sup.1 to R.sup.4 independently represent a
substituted or unsubstituted C1 to C6 aliphatic group, X is
selected from the group consisting of a hydrogen, a substituted or
unsubstituted aliphatic group, an acyl group, an oxy radical, a
hydroxyl group, an alkoxy group a --OSO.sub.2-alkyl group, and an
acyloxy group; L is a divalent linking group, linked to the
six-membered ring optionally by a double bond, wherein said
divalent linking group comprises a nitrogen-nitrogen or
nitrogen-oxygen bond; and
[0043] R represents a non-aromatic moiety comprising at least two
hydroxyl groups.
[0044] Further advantages and embodiments of the present invention
will become apparent from the following description.
DETAILED DESCRIPTION OF THE INVENTION
Definitions
[0045] The term divalent linking group as used in disclosing the
present invention refers to a linkage group linking two entities by
covalent bonds, regardless of whether the linkage group is linked
to each of these entities via a single, double or triple bond.
[0046] The term alkyl means all variants possible for each number
of carbon atoms in the alkyl group i.e. for three carbon atoms:
n-propyl and isopropyl; for four carbon atoms: n-butyl, isobutyl
and tertiary-butyl; for five carbon atoms: n-pentyl,
1,1-dimethyl-propyl, 2,2-dimethylpropyl and 2-methyl-butyl etc.
[0047] The term acyl group as used in disclosing the present
invention means --(C.dbd.O)-aryl and --(C.dbd.O)-alkyl groups.
[0048] The term aliphatic group includes straight chain, branched
chain and alicyclic hydrocarbon groups, which may contain at least
one double or triple bond, but are not aromatic.
Ink-recording Material
[0049] The different layers and particular ingredients of the
ink-recording material, according to the present invention, will
now be explained in detail.
Support
[0050] The support for use in the present invention can be chosen
from paper type and polymeric type supports well-known from
photographic technology. Paper types include plain paper, cast
coated paper, polyethylene coated paper and polypropylene coated
paper. Polymeric supports include cellulose acetate propionate or
cellulose acetate butyrate, polyesters such as polyethylene
terephthalate and polyethylene naphthalate, polyamides,
polycarbonates, polyimides, polyolefins, poly(vinylacetals),
polyethers and polysulfonamides. Other examples of useful
high-quality polymeric supports for the present invention include
opaque white polyesters and extrusion blends of polyethylene
terephthalate and polypropylene. Polyester film supports and
especially poly(ethylene terephthalate) are preferred because of
their excellent properties of dimensional stability. When such a
polyester is used as the support material, a subbing layer may be
employed to improve the bonding of the ink-receiving layer to the
support. Useful subbing layers for this purpose are well known in
the photographic art and include, for example, polymers of
vinylidene chloride such as vinylidene
chloride/acrylonitrile/acrylic acid terpolymers or vinylidene
chloride/methyl acrylate/itaconic acid terpolymers.
Ink-receiving Layer and Optional Auxiliary Layers
[0051] The ink-receiving layer contains, apart from a binder, a
light-stabilizer according to formula (I) as disclosed above. The
light-stabilizers are preferably added to the coating solution of
the ink-receiving layer as aqueous solutions. The amount of the
light-stabilizer in the receiving layer is preferably comprised
between 0.5 and 3 g/m.sup.2. A mixture of two or more
light-stabilizers may be used. Mixtures of two or more binders can
also be used in the receiving layer.
[0052] The ink-receiving layer may consist of just one single
layer, or alternatively it may be composed of two layers or even of
multiple layers. A particular type of an extra top ink-receiving
layer may be designated as a so-called "gloss improving layer",
meaning a layer which achieves a gloss of more than 30 at a
60.degree. angle. This gloss property can be achieved by the use of
swellable polymers and/or (in)organic pigments with a particle size
smaller than 500 nm.
[0053] In the case of double or multiple ink-receiving layers the
light-stabilizer may be incorporated in just one layer, or in
several layers or in all layers. It may also be present in
additional auxiliary layers, if present, such as an anti-curl
backing layer.
[0054] The ink-receiving layer or in at least one of the
ink-receiving layers, in the case of multiple layers, according to
the present invention, may further contain a pigment.
[0055] The ink-receiving layer or in at least one of the
ink-receiving layers, in the case of multiple layers, according to
the present invention, may also further contain a cationic
substance acting as mordant.
[0056] The ink-receiving layer, and an optional auxiliary layer,
such as a backing layer for anti-curl purposes, may further contain
well-known conventional ingredients, such as surfactants serving as
coating aids, hardening agents, plasticizers, whitening agents and
matting agents.
[0057] The ink-receiving layer and the optional auxiliary layer(s)
may also be crosslinked to provide such desired features as
waterfastness and non-blocking characteristics. The crosslinking is
also useful in providing abrasion resistance and resistance to the
formation of fingerprints on the element as a result of
handling.
[0058] The different layers can be coated onto the support by any
conventional coating technique, such as dip coating, knife coating,
extrusion coating, spin coating, slide hopper coating and curtain
coating.
Binder
[0059] The binder can be chosen from a list of compounds well-known
in the art including hydroxyethyl cellulose; hydroxypropyl
cellulose; hydroxyethylmethyl cellulose; hydroxypropyl methyl
cellulose; hydroxybutylmethyl cellulose; methyl cellulose; sodium
carboxymethyl cellulose; sodium carboxymethylhydroxethyl cellulose;
water soluble ethylhydroxyethyl cellulose; cellulose sulfate;
polyvinyl alcohol; vinylalcohol copolymers; polyvinyl acetate;
polyvinyl acetal; polyvinyl pyrrolidone; polyacrylamide;
acrylamide/acrylic acid copolymer; polystyrene, styrene copolymers;
acrylic or methacrylic polymers; styrene/acrylic copolymers;
ethylene-vinylacetate copolymer; vinylmethyl ether/maleic acid
copolymer; poly(2-acrylamido-2-methyl propane sulfonic acid);
poly(diethylene triamine-co-adipic acid); polyvinyl pyridine;
polyvinyl imidazole; polyethylene imine epichlorohydrin modified;
polyethylene imine ethoxylated; polyethylene oxide; polyurethane;
melamine resins; gelatin; carrageenan; dextran; gum arabic; casein;
pectin; albumin; starch; collagen derivatives; collodion and
agar-agar.
[0060] A preferred binder for the practice of the present invention
is a polyvinylalcohol (PVA), a vinylalcohol copolymer or modified
polyvinyl alcohol. Most preferably, the polyvinyl alcohol is a
cationic type polyvinyl alcohol, such as the cationic polyvinyl
alcohol grades from Kuraray, such as POVAL C506, POVAL C118, and
from Nippon Goshei.
Compound Represented by Formula (I)
[0061] According to a preferred embodiment of the ink-recording
material, according to the present invention, R is selected from
the group consisting of optionally substituted polyhydroxy
tetrahydro-pyrans, optionally substituted polyhydroxy
tetrahydrofurans, polyhydroxy straight chain alkyl groups,
polyhydroxy branched alkyl groups, polyhydroxy alkyl groups
substituted with optionally substituted tetrahydropyran groups and
polyhydroxy alkyl groups substituted with optionally substituted
tetrahydrofuran groups, wherein the carbon atoms in the chain may
be substituted with an oxygen atom, a sulfur atom or a --NR.sup.6--
group, where R.sup.6 is an alkyl group.
[0062] According to a preferred embodiment of the ink-recording
material, according to the present invention, L is selected from
the group consisting of a .dbd.N--NR.sup.7--C(.dbd.O)--,
--C(.dbd.O)--NR.sup.7--NR.- sup.8--C(.dbd.O)--, .dbd.N--O--,
.dbd.NR.sup.7--NR.sup.8--, --NR.sup.7--NR.sup.8--C(.dbd.O)--,
--(C.dbd.O)NR.sup.7--, --NR.sup.7--O--, .dbd.N--N.dbd.,
--C(.dbd.O)--NR.sup.7--O-- and .dbd.N--O--C(.dbd.O)-- groups,
wherein R.sup.7 and R.sup.8 independently represent a hydrogen atom
or an alkyl group.
[0063] According to a particularly preferred embodiment of the
ink-recording material, according to the present invention, L is
selected from the group consisting of .dbd.N--NH--,
--C(.dbd.O)--NH--NH--C(.dbd.O)- --, .dbd.N--O--,
.dbd.N--NH--C(.dbd.O)--, --NH--NH--C(.dbd.O)--,
--C(.dbd.O)--NH--O--, --NH--O--, .dbd.N--NCH.sub.3--C(.dbd.O)--,
--C(.dbd.O)--NH--NH--, .dbd.N--N.dbd. and
.dbd.N--O--C(.dbd.O)--NH-- groups.
[0064] According to a preferred embodiment of the ink-recording
material, according to the present invention, X is selected from
the group consisting of a hydrogen atom, a --O.sup.-,
--OSO.sub.2CH.sub.3, --C(.dbd.O)--CH.sub.3, --OC(.dbd.O)--CH.sub.3
and methoxy groups.
[0065] According to a preferred embodiment of the ink-recording
material, according to the present invention, R.sup.1, R.sup.2,
R.sup.3 and R.sup.4 are independently methyl or ethyl groups.
[0066] According to a preferred embodiment of the ink-recording
material, according to the present invention, Z is selected from
the group consisting of optionally substituted
--CH.sub.2--C(.dbd.)--CH.sub.2--, --CH.sub.2--CH(-)--CH.sub.2--,
--CH.dbd.C(-)--, --CH--C(.dbd.)-- and --CH--CH(-)-- groups.
[0067] According to a preferred embodiment of the compound
represented by formula (I), according to the present invention, the
ring is a six-membered ring to which L is covalently bonded by a
single or a double bond; formula (I) of the light-stabilizer then
becomes formula (II): 16
[0068] According to a further preferred embodiment of the compound
represented by formula (I), according to the present invention, the
ring is a five-membered ring with a double bond to which L is
covalently bonded by a single bond; formula (I) of the
light-stabilizer then becomes formula (III): 17
[0069] According to a further preferred embodiment of the compound
represented by formula (I), according to the present invention, the
ring is a five-membered ring to which L is covalently bonded by a
single or a double bond; formula (I) of the light-stabilizer then
becomes formula (IV): 18
[0070] According to a particularly preferred embodiment of the
compound represented by formula (I), according to the present
invention, L is a hydrazone or oxime moiety, giving rise to formula
(V): 19
[0071] wherein Y represents an oxygen atom or NR.sup.5 group;
R.sup.5 is selected from the group consisting of a hydrogen, a
substituted or unsubstituted, saturated or unsaturated aliphatic
group, a substituted or unsubstituted aromatic group, a substituted
or unsubstituted hetero-aromatic group, and an acyl group.
[0072] Useful light-stabilizers include:
1 20 Stabilizer 1 21 Stabilizer 2 22 Stabilizer 3 23 Stabilizer 4
24 Stabilizer 5 25 Stabilizer 6 26 Stabilizer 7 27 Stabilizer 8 28
Stabilizer 9 29 Stabilizer 10 30 Stabilizer 11 31 Stabilizer 12 32
Stabilizer 13 33 Stabilizer 14 34 Stabilizer 15 35 Stabilizer 16 36
Stabilizer 17 37 Stabilizer 18 38 Stabilizer 19 39 Stabilizer 20 40
Stabilizer 21 41 Stabilizer 22 42 Stabilizer 23 43 Stabilizer 24 44
Stabilizer 25 45 Stabilizer 26
[0073] A particularly preferred compound is stabilizer 1.
[0074] All light-stabilizing compounds according to the present
invention can be prepared according to well known synthetic
procedures, as illustrated by some synthetic schemes for the
preparation of preferred compounds. The synthetic strategies are
illustrated with a few general schemes, followed by a detailed
description of the synthesis of preferred compounds.
[0075] HALS-hydrazones and HALS-hydrazides can be prepared
according to general scheme 1. 46
[0076] wherein R' represents a non aromatic moiety comprising at
least two hydroxyl groups.
[0077] Hydrazinolysis of commercially available
saccharide-lactones, such as gluconolactone, ribonic lactone and
pantolactone, or esters of hydroxy-carboxylic acids yields the
required intermediate hydrazides. These intermediate hydrazides
smoothly react with 2,2,6,6-tetramethyl-4-p- iperidone, yielding
oligohydroxy substituted HALS-compounds, according to the present
invention. Hydrazones can be readily reduced to hydrazides, using
conventional reductants, such as NaBH.sub.3CN (Calabretta et al.,
Synthesis, 1991, 536-539), Et.sub.3SiH (Wu et al., Synthesis, 1995,
435-438), NaBH.sub.4 (J. Org. Chem., 1972, 37, 3615) and catalytic
hydrogenation (J. Am. Chem. Soc., 1992, 114, 6266).
[0078] Using the same intermediate hydrazides,
oligo-hydroxy-HALS-compound- s, having a diacyl hydrazide linking
group, can be prepared as illustrated in scheme 2. 47
[0079] O-alkylated HALS-oximes according to the present invention
can be prepared according to scheme 3. 48
[0080] where R represents a non aromatic moiety comprising at least
two hydroxyl groups.
[0081] The intermediate oxime is readily prepared by reacting
hydroxylamine with 2,2,6,6-tetramethyl-4-piperidone, followed by
alkylation, using 1,8-diazobicyclo[5.4.0.]undec-7-ene (DBU) or
sodium methanolate as base. Intermediate protection of the alcohols
and deprotection in the last synthetic step can be used if
required. The HALS-oximes can be further reduced to hydroxylamines
by conventional reductants.
[0082] Synthesis of stabilizer 1: 49
[0083] 44.5 g (0.25 mol) of gluconolactone was suspended in 375 ml
of ethanol. A solution of 18.75 g (0.375 mol) hydrazine hydrate in
125 ml ethanol was added to this suspension. The reaction mixture
was refluxed for 6 hours. After cooling down to room temperature,
the precipitated product was isolated by filtration. The crude
hydrazide was redissolved in 50 ml of water and precipitated with
400 ml of methanol. The precipitated hydrazide was isolated by
filtration, washed with 100 ml of methanol/water 10/1 and dried
under reduced pressure. 40 g (76%) of the hydrazide was isolated
(m.p.: 147-148.degree. C.).
[0084] 8.4 g (40 mmol) of the intermediate hydrazide and 7.6 g (40
mmol) of 2,2,6,6-tetramethyl-4-piperidone chlorohydrate were
dissolved in 100 ml of water. The reaction was allowed to continue
for 2 hours at room temperature. After 2 hours, water was
evaporated under reduced pressure. The residue was treated with
toluene and evaporated again. After treatment with ethanol and
evaporation, 11 g (79%) of the HALS-hydrazone was isolated as a
chlorohydrate.
Pigments
[0085] The pigment used is preferably an inorganic pigment, which
can be chosen from neutral, anionic and cationic pigment types.
Useful pigments include e.g. silica, talc, clay, hydrotalcite,
kaolin, diatomaceous earth, calcium carbonate, magnesium carbonate,
basic magnesium carbonate, aluminosilicate, aluminum trihydroxide,
aluminum oxide (alumina), titanium oxide, zinc oxide, barium
sulfate, calcium sulfate, zinc sulfide, satin white, alumina
hydrate such as boehmite, zirconium oxide or mixed oxides.
Preferably, the pigment is a cationic type pigment selected from
alumina hydrates, aluminum oxides, aluminum hydroxides, aluminum
silicates, and cationically modified silicas.
[0086] A preferred type of alumina hydrate is crystalline boehmite,
or .gamma.-AlO (OH). Useful types of boehmite include, in powder
form, DISPERAL, DISPERAL HP14 and DISPERAL 40 from Sasol, MARTOXIN
VPP2000-2 and GL-3 from Martinswerk GmbH.; liquid boehmite alumina
systems, e.g. DISPAL 23N4-20, DISPAL 14N-25, DISPERAL AL25 from
Sasol. Patents on alumina hydrate include EP 500021, EP 634286,
U.S. Pat. No. 5,624,428, EP 742108, U.S. Pat. No. 6,238,047, EP
622244, EP 810101, etc. Useful cationic aluminum oxide (alumina)
types include .alpha.-Al.sub.2O.sub.3 types, such as NORTON E700,
available from Saint-Gobain Ceramics & Plastics, Inc, and
.gamma.-Al.sub.2O.sub.3 types, such as ALUMINUM OXID C from
Degussa; other aluminum oxide grades, such as BAIKALOX CR15 and
CR30 from Baikowski Chemie; DURALOX grades and MEDIALOX grades from
Baikowski Chemie, BAIKALOX CR80, CR140, CR125, B105CR from
Baikowski Chemie; CAB-O-SPERSE PG003 trademark from Cabot, CATALOX
GRADES and CATAPAL GRADES from from Sasol, such as PLURALOX
HP14/150; colloidal Al.sub.2O.sub.3 types, such as ALUMINASOL 100;
ALUMINASOL 200, ALUMINASOL 220, ALUMINASOL 300, and ALUMINASOL 520
trademarks from Nissan Chemical Industries or NALCO 8676 trademark
from ONDEO Nalco.
[0087] Other useful cationic inorganic pigments include aluminum
trihydroxides such as Bayerite, or .alpha.-Al(OH).sub.3, such as
PLURAL BT, available from Sasol, and Gibbsite, or
.gamma.-Al(OH).sub.3, such as MARTINAL grades from Martinswerk
GmbH, MARTIFIN grades, such as MARTIFIN OL104, MARTIFIN OL 107 and
MARTIFIN OL111 from Martinswerk GmbH, MICRAL grades, such as MICRAL
1440, MICRAL 1500; MICRAL 632; MICRAL 855; MICRAL 916; MICRAL 932;
MICRAL 932CM; MICRAL 9400 from JM Huber company; HIGILITE grades,
e.g. HIGILITE H42 or HIGILITE H43M from Showa Denka K.K.
[0088] Another useful type of cationic pigment is zirconium oxide
such as NALCO OOSS008 trademark of ONDEO Nalco, acetate stabilized
ZrO.sub.2, ZR20/20, ZR50/20, ZR100/20 and ZRYS4 trademarks from
Nyacol Nano Technologies.
[0089] Useful mixed oxides are SIRAL grades from Sasol, colloidal
metal oxides from Nalco such as Nalco 1056, Nalco TX10496, Nalco
TX11678.
[0090] Another preferred type of inorganic pigment is silica which
can be used as such in its anionic form or after cationic
modification. Silica as pigment in ink receiving elements is
disclosed in numerous old and recent patents, e.g. U.S. Pat. No.
4,892,591, U.S. Pat. No. 4,902,568, EP 373573, EP 423829, EP
487350, EP 493100, EP 514633, etc. The silica can be chosen from
different types, such as crystalline silica, amorphous silica,
precipitated silica, fumed silica, silica gel, spherical and
non-spherical silica. The silica may contain minor amounts of metal
oxides from the group Al, Zr, Ti. Useful types include AEROSIL OX50
(BET surface area 50.+-.15 m.sup.2/g, average primary particle size
40 nm, SiO.sub.2 content>99.8%, Al.sub.2O.sub.3
content<0.08%), AEROSIL MOX170 (BET surface area 170 g/m.sup.2,
average primary particle size 15 nm, SiO.sub.2 content>98.3%,
Al.sub.2O.sub.3 content 0.3-1.3%), AEROSIL MOX80(BET surface area
80.+-.20 g/m.sup.2, average primary particle size 30 nm, SiO.sub.2
content>98.3%, Al.sub.2O.sub.3 content 0.3-1.3%), or other
hydrophilic AEROSIL grades available from Degussa-Huls AG, which
may give aqueous dispersions with a small average particle size
(<500 nm).
[0091] Cationically modified silica can be prepared by following
methods, without meaning to be limitative:
[0092] (1) subjecting silica to a surface treatment with an
inorganic cationic compound such as particular metal oxides and
oxyhydroxides, e.g. aluminum oxides, and alumina hydrates such as
boehmite and pseudo-boehmite; a useful cationic inorganic compound
to modify silica is pseudo-boehmite. Pseudo-boehmite is also called
boehmite gel and is fine particulate alumina hydrate having a
needle form. The composition thereof is generally represented by
Al.sub.2O.sub.3. 1.5-2 H.sub.2O and differs from that of
crystalline boehmite;
[0093] (2) by subjecting silica to a surface treatment with an
organic compound having both an amino group or quaternary ammonium
group thereof or a quaternary phosphonium group, and a functional
group having reactivity to a silanol group on the surface of
silica, such as aminoalkoxysilane or aminoalkyl glycidyl ether or
isopropanol amine;
[0094] (3) by polymerisation of a cationic or amino functional
monomer in the presence of a silica.
[0095] In an alternative embodiment the pigment may be chosen from
organic particles such as polystyrene, polymethyl methacrylate,
silicones, melamine-formaldehyde condensation polymers,
urea-formaldehyde condensation polymers, polyesters and polyamides.
Mixtures of inorganic and organic pigments can be used. However,
most preferably the pigment is an inorganic pigment.
[0096] Mixtures of two or more pigments may be used.
[0097] For obtaining glossy ink-receiving layers the particle size
of the pigment should preferably be smaller than 500 nm. In order
to obtain a porous glossy layer which can serve as an ink-receiving
layer for fast ink uptake the pigment/binder ratio should be at
least 4. Only at these high ratios the binder is no longer able to
fill up all pores and voids created by the pigments in the coating.
To achieve a sufficient porosity of the coating for fast ink uptake
the pore volume of these highly pigmented coatings should be higher
than 0.1 ml/g of coated solids. This pore volume can be measured by
gas adsorption (nitrogen) or by mercury diffusion.
Cationic Substance Acting as a Mordant
[0098] Cationic substances acting as a mordant increase the
capacity of the layer for fixing and holding the dye of the ink
droplets. A particularly suited compound is a
poly(diallyldimethylammonium chloride) or, in short, a
poly(DADMAC). These compounds are commercially available from
several companies, e.g. Aldrich, Nalco, CIBA, Nitto Boseki Co.,
Clariant, BASF and EKA Chemicals. Other useful cationic compounds
include DADMAC copolymers such as copolymers with acrylamide, e.g
NALCO 1470 trade mark of ONDEO Nalco or PAS-J-81, trademark of
Nitto Boseki Co., such as copolymers of DADMAC with acrylates, such
as Nalco 8190, trademark of ONDEO Nalco; copolymers of DADMAC with
SO.sub.2, such as PAS-A-1 or PAS-92, trademarks of Nitto Boseki
Co., copolymer of DADMAC with maleic acid, e.g. PAS-410, trademark
of Nitto Boseki Co., copolymer of DADMAC with
diallyl(3-chloro-2-hydroxypropyl)amine hydrochloride, eg. PAS-880,
trademark of Nitto Boseki Co., dimethylamine-epichlorohydrine
copolymers, e.g. Nalco 7135, trademark of ONDEO Nalco or POLYFIX
700, trade name of Showa High Polymer Co.; other POLYFIX grades
which could be used are POLYFIX 601, POLYFIX 301, POLYFIX 301A,
POLYFIX 250WS, and POLYFIX 3000; NEOFIX E-117, trade name of Nicca
Chemical Co., a polyoxyalkylene polyamine dicyanodiamine, and
REDIFLOC 4150, trade name of EKA Chemicals, a polyamine; MADAME
(methacrylatedimethylaminoethyl=dim- ethylaminoethyl methacrylate)
or MADQUAT (methacryloxyethyltrimethylammoni- um chloride) modified
polymers, e.g. ROHAGIT KL280, ROHAGIT 210, ROHAGIT SL144, PLEX
4739L, PLEX 3073 from Rohm, DIAFLOC KP155 and other DIAFLOC
products from Diafloc Co., and BMB 1305 and other BMB products from
EKA chemicals; cationic epichlorohydrin adducts such as POLYCUP 171
and POLYCUP 172, trade names from Hercules Co.; from Cytec
industries: CYPRO products, e.g. CYPRO 514/515/516, SUPERFLOC
507/521/567; cationic acrylic polymers, such as ALCOSTAT 567,
trademark of CIBA, cationic cellulose derivatives such as CELQUAT
L-2OO, H-1OO, SC-240C, SC-230M, trade names of Starch &
Chemical Co., and QUATRISOFT LM200, UCARE polymers JR125, JR400,
LR400, JR30M, LR30M and UCARE polymer LK; fixing agents from Chukyo
Europe: PALSET JK-512, PALSET JK512L, PALSET JK-182, PALSET JK-220,
WSC-173, WSC-173L, PALSET JK-320, PALSET JK-320L and PALSET JK-350;
polyethyleneimine and copolymers, e.g. LUPASOL, trade name of BASF
AG; triethanolamine-titanium-chelate, e.g. TYZOR, trade name of Du
Pont Co.; copolymers of vinylpyrrolidone such as VIVIPRINT 111,
trade name of ISP, a methacrylamido propyl dimethylamine copolymer;
with dimethylaminoethylmethacrylate such as COPOLYMER 845 and
COPOLYMER 937, trade names of ISP; with vinylimidazole, e.g.
LUVIQUAT CARE, LUVITEC 73W, LUVITEC VPI55 K18P, LUVITEC VP155 K72W,
LUVIQUAT FC905, LUVIQUAT FC550, LUVIQUAT HM522, and SOKALAN HP56,
all trade names of BASF AG; polyamidoamines, e.g. RETAMINOL and
NADAVIN, trade marks of Bayer AG; phosphonium compounds such as
disclosed in EP 609930 and other cationic polymers such as NEOFIX
RD-5, trademark of Nicca Chemical Co.
Surfactants
[0099] Surfactants may be incorporated in the layers of the
recording element of the present invention. They can be any of the
cationic, anionic, amphoteric, and non-ionic ones as described in
JP-A 62-280068 (1987). Examples of the surfactants are N-alkylamino
acid salts, alkylether carboxylic acid salts, acylated peptides,
alkylsulfonic acid salts, alkylbenzene and alkylnaphthalene
sulfonic acid salts, sulfosuccinic acid salts, .alpha.-olefin
sulfonic acid salts, N-acylsulfonic acid salts, sulfonated oils,
alkylsulfonic acid salts, alkylether sulfonic acid salts,
alkylallylethersulfonic acid salts, alkylamidesulfonic acid salts,
alkylphosphoric acid salts, alkyletherphosphoric acid salts,
alkylallyletherphosphoric acid salts, alkyl and
alkylallylpolyoxyethylene ethers, alkylallylform-aldehyde condensed
acid salts, alkylallylethersulfonic acid salts, alkylamidesulfonic
acid salts, alkylphosphoric acid salts, alkyletherphosphoric acid
salts, alkylallyletherphosphoric acid salts, alkyl and
alkylallylpolyoxyethylene ethers, alkylallylformaldehyde condensed
polyoxyethylene ethers, blocked polymers having polyoxypropylene,
polyoxyethylene polyoxypropylalkylethers, polyoxyethyleneether of
glycolesters, polyoxyethylene-ether of sorbitanesters,
polyoxyethyleneether of sorbitolesters, poly-ethyleneglycol
aliphatic acid esters, glycerol esters, sorbitane esters,
propyleneglycol esters, sugaresters, fluoro C.sub.2-C.sub.10
alkyl-carboxylic acids, disodium N-perfluorooctanesulfonyl
glutamate, sodium
3-(fluoro-C.sub.6-C.sub.11-alkyl-oxy)-1-C.sub.3-C.sub.4 alkyl
sulfonates, sodium
3-(.omega.-fluoro-C.sub.6-C.sub.8alkanoyl-N-ethylamino- )-1-propane
sulfonates, N-[3-(perfluorooctanesulfonamide)-propyl]-N,N-dime-
thyl-N-carboxymethylene ammonium betaine, fluoro-C.sub.11-C.sub.20
alkylcarboxylic acids, perfluoro-C.sub.7-C.sub.13-alkyl-carboxylic
acids, perfluorooctane sulfonic acid diethanolamide, Li, K and Na
perfluoro-C.sub.4-C.sub.12-alkyl sulfonates,
N-propyl-N-(2-hydroxyethyl)p- erfluorooctane sulfonamide,
perfluoro-C.sub.6-C.sub.10-alkylsulfonamide-pr-
opyl-sulfonyl-glycinates,
bis-(N-perfluorooctylsulfonyl-N-ethanolaminoethy- l)phosphonate,
mono-perfluoro C.sub.6-C.sub.16 alkyl-ethyl phosphonates and
perfluoroalkyl-betaine.
[0100] Useful cationic surfactants include N-alkyl dimethyl
ammonium chloride, palmityl trimethyl ammonium chloride,
dodecyldimethylamine, tetradecyldimethylamine, ethoxylated alkyl
guanidine-amine complex, oleamine hydroxypropyl bistrimonium
chloride, oleyl imidazoline, stearyl imidazoline, cocamine acetate,
palmitamine, dihydroxyethylcocamine, cocotrimonium chloride, alkyl
polyglycolether ammonium sulphate, ethoxylated oleamine, lauryl
pyridinium chloride, N-oleyl-1,3-diaminoprop- ane, stearamidopropyl
dimethylamine lactate, coconut fatty amide, oleyl hydroxyethyl
imidazoline, isostearyl ethylimidonium ethosulphate,
lauramidopropyl PEG-dimoniumchloride phosphate, palmityl
trimethylammonium chloride, and cetyltrimethylammonium bromide.
[0101] Especially useful are the fluorocarbon surfactants as
described in e.g. U.S. Pat. No. 4,781,985, having a structure of:
F(CF.sub.2).sub.4-9CH.sub.2CH.sub.2SCH.sub.2CH.sub.2N.sup.+R.sub.3X.sup.-
wherein R is a hydrogen or an alkyl group; and in U.S. Pat. No.
5,084,340, having a structure of:
CF.sub.3(CF.sub.2).sub.mCH.sub.2CH.sub.-
2O(CH.sub.2CH.sub.2O).sub.nR wherein m=2 to 10; n=1 to 18; R is
hydrogen or an alkyl group of 1 to 10 carbon atoms. These
surfactants are commercially available from DuPont and 3M. The
concentration of the surfactant component in the ink-receiving
layer is typically in the range of 0.1 to 2%, preferably in the
range of 0.4 to 1.5% and is most preferably 0.75% by weight based
on the total dry weight of the layer.
Plasticizers
[0102] The ink-receiving layer and the optional auxiliary layer(s)
may also comprise a plasticizer such as ethylene glycol, diethylene
glycol, propylene glycol, polyethylene glycol, glycerol
monomethylether, glycerol monochlorohydrin, ethylene carbonate,
propylene carbonate, urea phosphate, triphenylphosphate,
glycerol-monostearate, propylene glycol monostearate,
tetramethylene sulfone, n-methyl-2-pyrrolidone,
n-vinyl-2-pyrrolidone.
Crosslinking Agents
[0103] There are a vast number of known crosslinking agents--also
known as hardening agents--that will function to crosslink film
forming binders. Hardening agents can be used individually or in
combination and in free or in blocked form. A great many hardeners,
useful for the present invention, are known, including formaldehyde
and free dialdehydes, such as succinaldehyde and glutaraldehyde,
blocked dialdehydes, active esters, sulfonate esters, active
halogen compounds, isocyanate or blocked isocyanates,
polyfunctional isocyanates, melamine derivatives, s-triazines and
diazines, epoxides, active olefins having two or more active bonds,
carbodiimides, zirconium complexes, e.g. BACOTE 20, ZIRMEL 1000 or
zirconium acetate, trademarks of MEL Chemicals, titanium complexes,
such as TYZOR grades from DuPont, isoxazolium salts subsituted in
the 3-position, esters of 2-alkoxy-N-carboxy-dihydroquinoline,
N-carbamoylpyridinium salts, hardeners of mixed function, such as
halogen-substituted aldehyde acids (e.g. mucochloric and mucobromic
acids), onium substituted acroleins and vinyl sulfones and
polymeric hardeners, such as dialdehyde starches and
copoly(acroleinmeth-acrylic acid), and oxazoline functional
polymers, e.g. EPOCROS WS-500, and EPOCROS K-1000 series, and
maleic anhydride copolymers, e.g. GANTREZ AN119.
[0104] In the practice of this invention boric acid is a preferred
crosslinker.
[0105] The present invention will now be illustrated by the
following examples without however being limited thereto.
EXAMPLE 1
Preparation of the Coating Solution
[0106] To apply the light-stabilizing agent to ink jet print media,
a coating liquid was prepared by adding 25 parts by solid weight of
a 10% aqueous solution of compound Stabilizer 1 (ST1) (see list of
stabilizers in the Detailed Description section) to 170 parts of
water.
[0107] Coating and evaluation of the coated samples:
[0108] The coating solution was applied to a glossy porous media
(Agfajet Universal Instant Dry Photograde Paper Glossy) as the base
coat. In order to change the concentration of the light-stabilizing
additive, the thickness of the applied coating solution was varied.
The application was performed by means of a doctor blade coater.
The comparative samples were obtained by simply applying the
aqueous solution to the recording media without the stabilizing
agent.
[0109] After the media were allowed to dry at room temperature for
24 hours, color patches with 50% and 100% ink of cyan, magenta,
yellow and black were printed by means of a printer HP970Cxi
(trademark of Hewlett-Packard). The black patches were obtained by
printing cyan, magenta and yellow. The light-fastness was evaluated
by measuring the relative optical density loss of the printed
samples after being exposed to light in a fade-o-meter, XENOTEST
150 (trademark: Original Hanau) with 180 kLux during 16 hours. The
results are summarised in table 1.
2TABLE 1 comparison of optical density loss of printed media (50%
patches) treated with and without light-stabilizing additive:
Relative optical density loss (%) With 0.5 g/m.sup.2 Color Without
ST-1 of ST-1 with 1.5 g/m.sup.2 of ST-1 Yellow 24.0 15.1 14.8
Magenta 31.0 14.8 16.1 Cyan 28.6 23.5 26.9 Black 26.8 10.7 12.5
[0110] As can be seen from the table, the porous material
impregnated with stabilizer ST-1 shows an important improvement in
light-fastness.
EXAMPLE 2
[0111] Two ink jet recording media (invention and comparative) were
prepared by coating on a resin-coated paper an ink-receiving layer
which composition is shown in table 2. The coating weight of the
inorganic pigment was 30.0 g/m.sup.2. On top of this layer, a gloss
improving layer was coated containing 100 parts of the commercial
boehmite DISPERAL HP 14/2, from Sasol Co., a 25% dispersion in
water, 2 parts of a polyvinyl alcohol from Nippon Goshei Co., 0.2
parts of boric acid and 0.8 parts of cetyl-ammonium bromide. The
coating thickness was chosen to achieve a pigment coating weight of
5 g/m.sup.2. The invention sample contained 20 parts ST-1 in the
top layer, the comparative sample not.
3TABLE 2 Compositions Alumina (Cab-o-Sperse PG003: 40%, supplied by
Cabot 704.3 g Corp.) Polyvinyl alcohol (Gohsefimer K210, supplied
by Nippon 18.3 g Gohsei) Pseudo-boehmite DISPERAL P3 (trade name of
Sasol Co.) 28.2 g Boric acid 1.8 g Deionised water 477.5 g
[0112] Color patches with 50% and 100% ink of cyan, magenta, yellow
and black were printed on both samples by means of a of a printer
HP970Cxi (trademark of Hewlett-Packard). The light-fastness was
evaluated by measuring the relative optical density loss of the
printed samples after being exposed to light in a fade-o-meter,
XENOTEST 150 (trademark of Original Hanau) with 180 kLux during 16
hours.
[0113] The relative loss (%) in density of the four 50% color
patches together, due to the light fading are shown in table 3.
4 TABLE 3 Color Comparative sample Invention sample Yellow 42.3
42.6 Magenta 80.3 66.1 Cyan 49.0 50.0 Black 54.4 47.5
[0114] As can be seen, the color stability, especially for the
magenta ink and the black color (obtained from cyan, magenta and
yellow ink), was much improved when compound ST-1 was introduced in
the ink-receiving layer.
[0115] Having described in detail preferred embodiments of the
current invention, it will now be apparent to those skilled in the
art that numerous modifications can be made therein without
departing from the scope of the invention as defined in the
following claims.
[0116] All references, including publications, patent applications,
and patents, cited herein are hereby incorporated by reference to
the same extent as if each reference were individually and
specifically indicated to be incorporated by reference and were set
forth in its entirety herein.
[0117] The use of the terms "a" and "an" and "the" and similar
referents in the context of describing the invention (especially in
the context of the following claims) are to be construed to cover
both the singular and the plural, unless otherwise indicated herein
or clearly contradicted by context. Recitation of ranges of values
herein are merely intended to serve as a shorthand method of
referring individually to each separate value falling within the
range, unless otherwise indicated herein, and each separate value
is incorporated into the specification as if it were individually
recited herein. All methods described herein can be performed in
any suitable order unless otherwise indicated herein or otherwise
clearly contradicted by context. The use of any and all examples,
or exemplary language (e.g., "such as") provided herein, is
intended merely to better illuminate the invention and does not
pose a limitation on the scope of the invention unless otherwise
claimed. No language in the specification should be construed as
indicating any non-claimed element as essential to the practice of
the invention.
[0118] Preferred embodiments of this invention are described
herein, including the best mode known to the inventors for carrying
out the invention. Of course, variations of those preferred
embodiments will become apparent to those of ordinary skill in the
art upon reading the foregoing description. The inventors expect
skilled artisans to employ such variations as appropriate, and the
inventors intend for the invention to be practiced otherwise than
as specifically described herein. Accordingly, this invention
includes all modifications and equivalents of the subject matter
recited in the claims appended hereto as permitted by applicable
law. Moreover, any combination of the above-described elements in
all possible variations thereof is encompassed by the invention
unless otherwise indicated herein or otherwise clearly contradicted
by context.
* * * * *